RTL1 and multiple congenital anomalies due to 14q32.2 maternally expressed gene defect: Our study clearly demonstrates that RTL1 is of crucial physiological significance because it plays a major role in the maturation and maintenance of fetal muscle fibers (Figs 2 and 4); therefore, its loss and overproduction affect the muscle phenotypes of Temple and Kagami-Ogata syndromes, respectively (Table 1 and Tables S1-S3).